Electric defroster for refrigerators



March w, 194.2o H. L. BEKER 2,276,454

ELECTRIC DEFROSTER FOR FRIGERATORS Filed March 9. i939 ATTOR N EYSPatented Mar. 17, ,1942

ELECTRIC DEFROSTER FCR REFRIGERATORS Harry, L. Becker, Council Grove,Kans. y Application March 9, 1939, Serial No.260,836v

' (ci. cs2-1)v 7 Claims.'

My invention relates to defrosting devices for refrigerators.

An important object of my invention is the provision of a defrostingdevice that will quickly and eiiiciently free the cooling coils of ice;

Another object of my invention is the provision of a defrosting devicethatf will expeditiously defrost the cooling unit with very little risein the temperature of the refrigerator.

Yet another object of my invention is the provision of a defrostingdevice that is expeditious in the defrosting action in a manner wherebythere will be no loss of perishable goods within the Vrefrigerator dueto an increased temperature therein during the defrosting of the coils.

Still another object of my invention is the provision of a defrostingdevice that is simple in construction, eicient inv operation andinexpensive to manufacture.

Other objects and advantages of my invention will be apparent during thecourse of the following description: 'f f1 Y In the drawing, formingfapart' of this specication, and in which likenumerals are employed todesignate like parts throughout the same- Figure 1 is a perspective viewof my device, showing its association with the cooling coils of arefrigerator,

extremities I1 terminate a substantial Adistance from each other toprovide a longitudinally extending slot I8. The longitudinal endsof thecasing are provided with tabs I9 which form a supporting means wherebythe said casing may I be securely attached to the cooling coils.

A strip 20 of a suitable electrical insulating material such as mica, orthe like, is positioned within the casing I5-and has the'heating coil 2|positioned 'spirally therearound and with the opposite ends 22 andl 23thereof attachedy to-terminals 24 and 25 which extend outwardly of thecasing. The strip of mica 20 has companion -Suitable heat insulatingmaterialZ such as asbestos-or thelike, is'packed around the stripswithin the" casing| 5fto hold "the heating coil 2| and protectiveelectricalwinsulatin'g lstrips l in the proper relative position, and todirect the heat generated .by the vsaid coil outwardly through theelongated slotl I8 in the casing in a manner Fig. 2 is a bottom planview of my device form of my invention associated therewith, and

Fig, 6 is a wiring diagram of the electrical circuit embodying a part ofmy invention.

In the accompanying drawing, wherein for the purpose of illustration, isshown preferred embodiments of. my invention, the numeral III designatesa refrigerator of conventional shape and construction and having thecooling coils II secured .therein to receive the ice trays I2. A frontpanel I3 is fastened to the forward part of the coils and has an openingI4 to permit ready access to be had to the trays I2.

My device comprises a casing I5 which is preferably formed from a pieceof sheet metal having the longitudinal edges I6 thereof bent inwardlyand with the extremities Il of the said edges bent inwardly in spacedparallel relation with the back of the casing. The ends of the toprevent the dispersion ofthe heat through the back ofthe casing and intothe refrigerator. The strip 21 is of sumcient width to vpermit eitherlongitudinal end thereof to be positioned behind the extremities Il ofthe casing in a manner whereby the various elements within the casingwill be securely held in place and with the heating coil 2| in appressedrelation therewi h.

While I have here described but one unit of my device, I prefer to usefour separate units in association with the cooling coil of therefrigerator in order that the best results be obtained and that, whileI have only described one of the units lin detail, it is 'to beunderstood that -all of the units are identical in their construction. Ihave found that-best results are obtained by placingspaced pairs ofheating'units on either side of the cooling' coiland with the elongatedslot I8 of the casing facing inwardly toward the coil.

In the wiring diagram, illustrated in Fig. 6, I

It is a wen known 'fact that it is essential to Athe eiiicient operationof the refrigerator that the cooling coils be periodically defrosted,and that in order to prevent perishable articles within the refrigeratorfrom being lost, it is necessary that this be accomplished in anexpeditious manner and with relatively little dispersion of the heatwithin the refrigerator. In my device the strip 21 will electricallyinsulate the heating coils from the cooling coils of the refrigeratorbut will in no way prevent the free dispersion of heat therethroughagainst the said cooling coils.

The cooling coils are frequently formed with spaced parallel tubes 30joined by an intervening web 3l and, in a coil constructed in thismanner, I find it advisable to provide a casing 32 which is corrugatedin its formation'ln a manner whereby the same may be placed in closefitting contact with the corrugated exterior of the coil. This y form ofthe invention is best illustrated in Fig. 5,

and the position of the parts within the casing 32 is so similar to therst form-of the invention, hereinbefore described, that furtherexplanation is. thought to be unnecessary. A

It is obvious that the electrical insulating strips within the casingmust be of undulatory formation in order to be properly received with'-in the casing 32.

It is to. be understoodv that the forms of my invention herewith shownand describedare to be taken as preferred `examples of the same, and

that various changes in the size, shape and relation of parts may beresorted to without .de-

parting from the spirit ofy my invention or the' scope of the appendedclaims.

Having thus' described my invention,- I claim:

1. In arefrigerator having a cooling coil, the combination of acasingsecured to the said coil and having an open side in` appressed confront;ing relation therewith,v a heating element within the casing adjacentthe open side thereof, electrical insulating', heat conducting materialin' terposed between the said heating=element and adjacent the opensides thereof, heat conducting means to electrically insulate theheating coils a from the said cooling coil, means to heat insulate4means to electrically insulate the heating coils the heating coils fromthe said casings in a manner to direct the heat from the heating coilsthrough the open sides of the casings and against the cooling coil, asource of electric lpower, an

velectric circuit connectingthe said heating coils and the said sourceof electric power, and manually operable switch means within saidcircuit.

4. In combination with a refrigerator having a cooling coil, pairs ofspaced casings having open'sides in confronting relation with the coiland secured thereto oneither side thereof, heat ing coils arrangedwithin the said casings adjacent the open sides thereof, heat conductingfrom the said cooling coil, means to heatinsulate the heating coils fromthe closed sides of the said casings, a source of electric power, and anelectric circuit connecting the said heating coils and connected to thesaid source of electric power.

5. In combination with a refrigerator having a cooling coil, means todefrost the said cooling coil comprising a casing secured to the coiland formed with anopen side confronting the coil.

. said casing being longitudinally corrugated to permit the same to havea close fitting engagement with the said coil, a heating element withinthe said casing, heat conducting, electrical insulating materialinterposed between the said heating element and the Vsaid cooling coil.and aheat insulating material interposed between the heating clement andthe said casing. v

6. In combination with a refrigerator having l a cooling coil, means todefrost said cooling coil comprising pairs of spaced casings having opensides facing the said coil and secured thereto on .either side thereof,a heating coil within each casing adjacent the open side thereof,thermally conducting means to electrically insulate the heating coilsfrom the said cooling coil, and

the said cooling coil, and a heat insulating material interposed betweenthe heating element and the closed sides of the said casing.

2. In a refrigerator having'a cooling coil, theheating coils arrangedwithin-.the said casings means to heat insulate the heating coils fromthe closed sides of said casings.

`'1. In combination with a refrigerator having a .cooling coil, means todefrost said cooling coil comprising pairs of spaced casings having opensides disposed in confronting relation withvthe said cooling coil andsecured thereto on either side thereof, heating coils arranged withinthe' said casings adjacent the open sides thereof, said heating coilsbeing electrically insulated from said cooling coils, and means to heatinsulate the heating coils from the closed sides of the said casings ina manner to direct the heat from the heating coils through the opensides and agains the said cooling coil.

f a HARRYLBECKER.'

